1 /*
   2  * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
   3  * @LastModified: Oct 2017
   4  */
   5 /*
   6  * Licensed to the Apache Software Foundation (ASF) under one or more
   7  * contributor license agreements.  See the NOTICE file distributed with
   8  * this work for additional information regarding copyright ownership.
   9  * The ASF licenses this file to You under the Apache License, Version 2.0
  10  * (the "License"); you may not use this file except in compliance with
  11  * the License.  You may obtain a copy of the License at
  12  *
  13  *      http://www.apache.org/licenses/LICENSE-2.0
  14  *
  15  * Unless required by applicable law or agreed to in writing, software
  16  * distributed under the License is distributed on an "AS IS" BASIS,
  17  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  18  * See the License for the specific language governing permissions and
  19  * limitations under the License.
  20  */
  21 
  22 package com.sun.org.apache.xalan.internal.xsltc.compiler;
  23 
  24 import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
  25 import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;
  26 import com.sun.org.apache.bcel.internal.generic.InstructionList;
  27 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
  28 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ErrorMsg;
  29 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
  30 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
  31 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
  32 import java.util.List;
  33 
  34 /**
  35  * @author Jacek Ambroziak
  36  * @author Santiago Pericas-Geertsen
  37  * @author Morten Jorgensen
  38  */
  39 final class StartsWithCall extends FunctionCall {
  40 
  41     private Expression _base = null;
  42     private Expression _token = null;
  43 
  44     /**
  45      * Create a starts-with() call - two arguments, both strings
  46      */
  47     public StartsWithCall(QName fname, List<Expression> arguments) {
  48         super(fname, arguments);
  49     }
  50 
  51     /**
  52      * Type check the two parameters for this function
  53      */
  54     public Type typeCheck(SymbolTable stable) throws TypeCheckError {
  55 
  56         // Check that the function was passed exactly two arguments
  57         if (argumentCount() != 2) {
  58             ErrorMsg err = new ErrorMsg(ErrorMsg.ILLEGAL_ARG_ERR,
  59                                         getName(), this);
  60             throw new TypeCheckError(err);
  61         }
  62 
  63         // The first argument must be a String, or cast to a String
  64         _base = argument(0);
  65         Type baseType = _base.typeCheck(stable);
  66         if (baseType != Type.String)
  67             _base = new CastExpr(_base, Type.String);
  68 
  69         // The second argument must also be a String, or cast to a String
  70         _token = argument(1);
  71         Type tokenType = _token.typeCheck(stable);
  72         if (tokenType != Type.String)
  73             _token = new CastExpr(_token, Type.String);
  74 
  75         return _type = Type.Boolean;
  76     }
  77 
  78     /**
  79      * Compile the expression - leave boolean expression on stack
  80      */
  81     public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
  82         final ConstantPoolGen cpg = classGen.getConstantPool();
  83         final InstructionList il = methodGen.getInstructionList();
  84         _base.translate(classGen, methodGen);
  85         _token.translate(classGen, methodGen);
  86         il.append(new INVOKEVIRTUAL(cpg.addMethodref(STRING_CLASS,
  87                                                      "startsWith",
  88                                                      "("+STRING_SIG+")Z")));
  89     }
  90 }